Generally a capacitor unit is used as support power source for high output power source in vehicle and others mounting fuel cells, and multiple capacitors are connected in series.
When employing such capacitor unit, a capacitor control system is needed for monitoring and controlling the voltage of individual capacitors and the total voltage of entire capacitors.
Hitherto, the capacitor control system includes individual detectors for detecting the voltage of individual capacitors for composing the capacitor unit, and the information obtained from the individual detectors is processed by microcomputer.
A prior art relating to the present application is disclosed, for example, in Japanese Patent Application Laid-Open No. H11-248755.
However, for processing of information corresponding to multiple capacitors by microcomputer, many ports are required in the microcomputer. To have enough ports, a plurality of microcomputers are needed, and the capacitor control system is increased in size.
It is hence an object of the invention to present a capacitor control system of small size.
In the description of the invention of the present application, the terms “capacitor” and “condenser” are used, and they are defined as synonyms. Namely, “condenser” is identical to “capacitor.” In other words, they are defined as passive elements for either accumulating or discharging electric energy by capacitance. The term “condenser” is generally interpreted as meaning a heat exchanger for condensing the heating medium in a freezer, etc., but let us add that the term is not used in that sense in the present invention.
In the description of the present invention, “capacitor” is defined as a constituent element of the capacitor unit, while “condenser” is used in the sense of an electricity accumulating element constituting a “detecting unit” provided for the purpose of detecting the electric charge accumulated in the capacitor.